The present invention relates to an operating element according to the definition of the species of the independent patent claim.
For personal computers, operating devices are known which have a spherical operating element, e.g., in the form of a computer mouse or a trackball, the latter preferably in portable personal computers. These devices are mostly used for two-dimensional input, e.g., for controlling the position of a pointer within a two-dimensional menu displayed on a computer monitor screen. The spherical operating element in such a known operating device is usually supported so that any translatory movement of the ball within the casing surrounding it is essentially suppressed.
In addition, International Patent Application WO-A 98/54670 describes an operating device having a spherical operating element in the form of a lockable trackball, the spherical operating element described there having at its surface trough-like recesses in which the catch elements engage. For the user, this permits improved haptic feedback regarding the extent of adjustment of the parameter adjusted with the spherical operating element. Visual control of the parameter to be adjusted can thus be eliminated under some circumstances. The device described here is therefore especially suitable,for use in such devices in which visual control of the parameters to be adjusted is difficult or impossible.
Finally, one-dimensional operating elements, e.g., in the form of rotary potentiometers or rotary increment encoders, which can rotate about an axis of rotation and permit an adjustment of one parameter, are also known. Various parameters to be adjusted can be assigned to such an operating element, e.g., through function keys.
One-dimensional rotary encoders having a positional memory fixedly predetermined by a locating spring and corresponding locating marks constitute another known embodiment of such one-dimensional operating elements.
The operating element according to the present invention having the features of the independent patent claim, namely an operating element having a first control element that can rotate about a first axis, wherein at least one second control element can rotate about a second axis which does not coincide with the first axis, has the advantage that two parameters can be adjusted independently of one another by using a single operating element. This permits, for example, control of a pointer in a two-dimensional menu, whereby in contrast with a single spherical operating element as a two-dimensional operating element, inadvertent adjustment in an unwanted dimension, e.g., as a result of vibration or a faulty optical feedback, is prevented by having only one dimension assigned to each control element of the operating element.
An especially advantageous embodiment of the operating element according to the present invention is characterized by the fact that the second control element has a rotationally symmetrical design and the at least two control elements are arranged so that the second control element surrounds the first control element at least in part. This has the advantage that the user can locate the additional control element(s) without any complicated searching through a slight translatory movement of the hand operating the element, even without direct visual contact with the operating element, based on the knowledge of the location of a first control element of the operating element.
Structuring of the surface of at least one of the control elements is especially advantageous because on the one hand the grip of the respective control element can be increased in this way, while on the other hand the user can be given a haptically mediated impression of the possible rotational degrees of freedom of the respective control element.
It is also advantageous to provide means for influencing the torque required to rotate at least one of the control elements of the operating element. In this way, the user can be provided with haptic feedback of the prevailing value of the parameter to be adjusted e.g., in adjustment of a parameter by way of the operating element, or he can be notified that he has arrived at an end of a value range of the parameter to be adjusted.
The latter case, i.e., haptic mediation of an impression through the dimension of a parameter setting, is possible in particular if a torque characteristic is generated via the means for influencing the torque required for rotation of at least one control element, thereby achieving engagement of the control element.
It is also advantageous that the spacings of the locating marks are not fixed in the case of an operating element according to the present invention, in contrast with the mechanical option mentioned in the preamble, but instead they can be varied as a function of the context, for example. Thus, when the operating element according to the present invention is used as a volume controller for a car radio, for example, a large number of locating marks can be distributed over a revolution of the operating element, which makes it possible to cover the entire volume range with a single revolution with a sufficiently high resolution. On the other hand, when using the operating element as a source switch for a car radio, for example, only a few locating marks, each being assigned to one audio source, could be distributed over one revolution of the operating element, thus yielding the conventional haptics for home audio systems, for example, with which the user is familiar.